Alpha Numeric: Level 1
1.
In the addition problem `3A + 5A = 88`, what is the digit A?
Solution (B): Look at the units column: \(A + A = 8\).
This means \(2A = 8\), so \(A = 4\).
Check the tens column: \(3 + 5 = 8\).
The problem is \(34 + 54 = 88\). This is correct.
2.
In the addition problem `A5 + 3A = 90`, what is the digit A?
Solution (A): Look at the units column: \(5 + A = 0\). This must be 10, so we carry a 1.
If \(5 + A = 10\), then \(A = 5\).
Check the tens column: \((A + 3) + 1(\text{carry}) = 9\).
\((5 + 3) + 1 = 8 + 1 = 9\). This is correct.
The problem is \(55 + 35 = 90\).
3.
In the addition problem `AA + BB = 66`, if A and B represent different digits, what is \(A+B\)?
Solution (C): This problem can be written as \((10A + A) + (10B + B) = 66\).
\(11A + 11B = 66\).
Factor out 11: \(11(A + B) = 66\).
Divide by 11: \(A + B = 6\).
4.
The four-digit number \(1,2X3\) is divisible by 3. Which of the following could be the digit X?
Solution (E): For a number to be divisible by 3, the sum of its digits must be a multiple of 3.
Sum = \(1 + 2 + X + 3 = 6 + X\).
We need \(6+X\) to be a multiple of 3. Since 6 is already a multiple of 3, X must also be a multiple of 3.
Possible values for X are {0, 3, 6, 9}.
Of the options given, only 9 is in this set.
5.
In the subtraction problem `A0 – 4A = 32`, what is the digit A?
Solution (B): Look at the units column. We have \(0 – A = 2\).
This means we must borrow from the tens place (A).
\(10 – A = 2\), which means \(A = 8\).
Check the tens column: We borrowed 1 from A, so it becomes \(A-1\).
\((A-1) – 4 = 3\).
Substitute \(A=8\): \((8-1) – 4 = 7 – 4 = 3\). This is correct.
The problem is \(80 – 48 = 32\).
6.
In the multiplication problem \(A \times 4 = 2A\), what is the digit A?
Solution (C): We are looking for a digit A such that \(A \times 4\) results in a two-digit number that ends in A.
Let’s test the options:
(A) \(4 \times 4 = 16\). This ends in 6, not 4.
(B) \(5 \times 4 = 20\). This ends in 0, not 5.
(C) \(6 \times 4 = 24\). This ends in 4, not 6.
*Correction:* Let’s re-read the problem. \(2A\) is a two-digit number.
The tens digit is 2, and the units digit is A.
Let’s test again:
(A) \(4 \times 4 = 16\). Does 16 = 2A = 24? No.
(B) \(5 \times 4 = 20\). Does 20 = 2A = 25? No.
(C) \(6 \times 4 = 24\). Does 24 = 2A = 26? No.
(D) \(7 \times 4 = 28\). Does 28 = 2A = 27? No.
(E) \(8 \times 4 = 32\). Does 32 = 2A = 28? No.
There is an error in my question creation. Let’s fix Q6.
`A \times 6 = 3A`.
Test: (A) 4: \(4 \times 6 = 24\). Does 24 = 34? No.
Test: (B) 5: \(5 \times 6 = 30\). Does 30 = 35? No.
Test: (C) 6: \(6 \times 6 = 36\). Does 36 = 36? Yes.
6.
In the multiplication problem \(A \times 6 = 3A\), where 3A is a two-digit number, what is the digit A?
Solution (C): We are looking for a digit A such that \(A \times 6\) results in a two-digit number that has a tens digit of 3 and a units digit of A.
Let’s test the options:
(A) \(4 \times 6 = 24\). This does not equal 34.
(B) \(5 \times 6 = 30\). This does not equal 35.
(C) \(6 \times 6 = 36\). This equals 3A (where A=6). This is correct.
(D) \(7 \times 6 = 42\). This does not equal 37.
(E) \(8 \times 6 = 48\). This does not equal 38.
7.
If \(A + B = 10\) and \(A \times B = 21\), and A and B are integers, what is the value of the smaller integer?
Solution (B): We need two numbers that multiply to 21 and add to 10.
The factor pairs of 21 are (1, 21) and (3, 7).
\(1 + 21 = 22\). (Incorrect)
\(3 + 7 = 10\). (Correct)
The two integers are 3 and 7. The smaller integer is 3.
8.
In the problem `AA + 55 = 77`, what is the digit A?
Solution (D): This is an algebra problem.
`AA` is \(10A + A = 11A\).
\(11A + 55 = 77\).
\(11A = 77 – 55\).
\(11A = 22\).
\(A = 2\).
Check: \(22 + 55 = 77\).
9.
In the problem `BA + 6B = CAB`, where C is a carry-over digit, what is the digit C?
Solution (A): Look at the tens column: \(B + 6\) results in \(CA\).
Since B and 6 are single digits, their sum must be less than 20 (e.g., \(9+6=15\)).
This means the carry-over digit \(C\) must be 1.
(We can solve the rest: Units: \(A+B=B \implies A=0\). Tens: \(B+6 = 1A = 10 \implies B=4\). Check: \(40 + 64 = 104\). This works. \(C=1\).)
10.
The three-digit number `5X1` is divisible by 3. Which of the following could be the digit X?
Solution (C): For a number to be divisible by 3, the sum of its digits must be a multiple of 3.
Sum = \(5 + X + 1 = 6 + X\).
We need \(6+X\) to be a multiple of 3. Since 6 is already a multiple of 3, X must also be a multiple of 3.
Possible values for X are {0, 3, 6, 9}.
Of the options given, only 3 is in this set.
Score: 0 / 10
